I got my first detector in 1969 and although it would only go maybe three inches deep on a coin, finding 100 coins in a day hunting schools, parks and playgrounds that had never had a detector in them wasn't a problem. Also dug a lot of trash as the detector would null on iron but detected everything else, not as bad as it would seem though as there wasn't nearly as much trash as there is now. I would be lucky to get 100 coins in a month hunting those same parks, schools and playgrounds now with any detector
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